Trona Pinnacles

The Trona Pinnacles is one of the most unusual geological features in the California Desert National Conservation Area. The unusual landscape consists of more than 500 tufa spires (porous rock formed as a deposit from springs of streams), some as high as , rising from the bed of the Searles Lake (dry) basin. The pinnacles vary in size and shape from short and squat to tall and thin, and are composed primarily of calcium carbonate (tufa). They now sit isolated and slowly crumbling away near the south end of the valley, surrounded by many square miles of flat, dried mud and with stark mountain ranges at either side.

Geography

The Trona Pinnacles, at an elevation of above sea level, are located approximately south of Trona, California. Access to the site is from a BLM dirt road (RM143) that leaves State Highway 178, about east of the intersection of State Highway 178 and the Trona-Red Mountain Road. The long dirt road from State Highway 178 to the Pinnacles is usually accessible to 2-wheel drive vehicles, however, the road may be closed during the winter months after a heavy rain.

Deep beneath Searles Lake, calcium-rich groundwater and alkaline lake water combined to grow tufa formations. Today you can see the rare aftermath of the perfect geological conditions.

Known as tufa pinnacles, these strange shapes formed underwater 10,000 to 100,000 years ago. The pinnacles did not all form at the same time. They are divided by age and elevation into three groups. The groups are dubbed the northern, middle, and southern groups because they formed during three ice ages.

The northern group is the youngest at 10,999 to 25,000 years old. These are the best examples of what are known as tufa towers. The northern youngsters also include shapes called tombstones, ridges and cones. Close cousins to the northern group, the small middle group claims only 100 spires, but boasts the tallest "tower", rising . The granddaddy of them all, the southern group, includes 200 tufa formations aged 32,000 to 100,000 years old.

People have historically given names to the strange forms. These ancient spires were once dubbed "Cathedral City". Geologically, the pinnacles are classified into four general shapes. Towers are taller than they are wide and rise 30 to . Tombstones are stubby and squat and rise 20 to . Most tombstones are in the northern-most tufa formations. Ridges are massive toothy tufa ruins. Trona has three ridges, one in the northern tufa cluster and two in the middle group. One ridge is long and wide and tall. Cones are less than tall. Dumpy and mounded, cone shapes lay scattered throughout the Trona Pinnacles.